It is well known that ethylenically unsaturated compounds readily polymerize when heated and that the polymerization rate increases with increasing temperature. A significant problem occurs during processing of hydrocarbon streams containing ethylenically unsaturated compounds, in particular butadiene, where thermal polymerization results in equipment fouling or agglomeration during the many stages of handling, purification, and storage.
Common industrial methods for producing ethylenically unsaturated monomers include a variety of purification processes, including distillation to remove impurities. Unfortunately, purification operations carried out at elevated temperatures result in an increased rate of undesired polymerization. Polymerization, such as thermal polymerization, during the monomer purification process, results not only in loss of desired monomer end-product, but also in loss of production efficiency caused by polymer formation or agglomeration on process equipment. In heat requiring operations, such agglomeration adversely affects heat transfer efficiency.